Spin-lattice relaxation in amorphous silicon. Evidence of anomalous temperature dependences
نویسندگان
چکیده
2014 We have investigated the spin-lattice relaxation of localized states in evaporated amorphous silicon films. Temperature and concentration dependences of the relaxation rate have been measured in the temperature range 4.2-290 K. Below 10 K a phonon bottleneck is present. Between 10 and 100 K, a single phonon process predominates. It can be accounted for assuming a significant exchange interaction. Above 100 K, spin-lattice relaxation is governed by hopping. J. Physique LETTRES 42 ( 1981 ) L-21 L-24 1 er JANVIER 1981,
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